1. Field of the Invention
The present invention relates to an inductive charging method for vehicles, particularly to the method which utilizes a frequency converter power sourcing (PS) module in a PS device to connect with a signal control circuit and a power source and series connected power receiving (PR) modules in a PR device to connect with a bleeder circuit and a PR output terminal, allowing vehicles to be wirelessly charged and identified, make comparisons of voltages, adjust power and transmit data, thus achieving the effect of convenience in use and prevention of electricity leakage and theft.
2. Description of the Related Art
Generally, most of electric vehicles are equipped with storage batteries inside. Such vehicles need to be charged when electricity in the storage batteries run out or is insufficient to use. Yet such charging method requires electric connections of vehicles with power lines and sockets. When charging stations are installed, it is very likely to cause leakages of electricity which may lead to electric shocks or problems of power consumption due to wet sockets with rainwater, in addition to possibilities that someone steals electricity from these sockets illegally. Therefore, as inductive charging technology has been developed and applied, and systems that transmit power inductively rely on DC power input to driving coils at the PS end to transmit electric energy to PR coils through AC electromagnetic waves, following procedures of rectification, filter and voltage stabilization, to provide DC power to electromechanical systems at the rear of the PR end, some firms try to apply the inductive charging technology in charging of electric vehicles.
However, electromechanical systems require high-voltage DC power to operate, and there is no way to raise the voltage at the PR output end with the inductive charging technology due to the following two reasons:                (1) the voltage outputted from the PR end originates from that of PR coils following procedures of rectification, filter and stabilization. As each of these procedures will result in voltage reduction following processing, if the output voltage is required to be raised at the PR end, the voltage of the PR coil at the initial end must be raised remarkably and rectifying components at the rear end are required to resist high voltage. Since high-voltage resistant components are very expensive and difficult to manufacture, this will cause much difficulty and too high costs in practice.        (2) if high voltage is needed on the PR coil, it indicates that it is necessary to provide high driving voltage on the PS coil to emit electric power. Under such circumstance, driving components at the PS end must be components capable of driving high voltage. Since the components of such kind are very expensive and difficult to manufacture, this will cause much difficulty and too high costs in practice.        
Thus, how to overcome the problems and advantages of high cost and high difficulty in raising output voltage at the PR end with inductive charging technology of conventional use is what the firms engaged in this field need urgently to research and improve.